Automated control systems attempt to drive physical characteristics of a system, for example a process or object, to achieve system objectives. Automated control systems may be able to improve on the control provided manually by a human operator, for example by providing a higher frequency response, by taking account of a greater number of system parameters, and/or by providing a higher accuracy of control. Automated control systems may take many forms and may be designed to use continuous time controllers and/or discrete time controllers. Control systems may be both designed and described with control diagrams representing processing blocks. Generally, a control system may be built and implemented from the control system diagram.
A well bore may be serviced using a work string. A work string may include continuous coiled tubing which is fed continuously into the well bore from large spools. The longer the continuous tubing, the greater the tensile strength of the tubing may be to support the weight of the longer tubing. On the other hand, the greater the tensile strength of the tubing, the less flexible the tubing may be and the greater stress that may be produced in the tubing as it flexes going into the well bore and coming back out of the well bore. An advantage of coiled tubing is that it can be fed relatively rapidly and continuously into a well bore. A work string may also be composed of interconnected pieces or joints of pipe, for example joints of pipe about 10 meters long with a male threaded end and an opposite female threaded end. The pipe joints are connected together by threading two pipe joints together tightly. Various tools may be attached to the end of the work string—either coiled tubing or interconnected joints of pipe—to accomplish a variety of well bore operations.